Re: Inheriting table AMs for partitioned tables - Mailing list pgsql-hackers

From Amit Langote
Subject Re: Inheriting table AMs for partitioned tables
Date
Msg-id 0d4282d6-0493-378c-e439-7108a3067942@lab.ntt.co.jp
Whole thread Raw
In response to Re: Inheriting table AMs for partitioned tables  (Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>)
List pgsql-hackers
On 2019/03/05 11:59, Amit Langote wrote:
> On 2019/03/05 8:47, Andres Freund wrote:
>> Hi,
>>
>> In the pluggable storage patch [1], one thing that I'm wondering about
>> is how exactly to inherit the storage AM across partitions. I think
>> that's potentially worthy of a discussion with a wider audience than I'd
>> get in that thread.  It seems also related to the recent discussion in [2]
>>
>> Consider (excerpted from the tests):
>>
>> CREATE TABLE tableam_parted_heap2 (a text, b int) PARTITION BY list (a) USING heap2;
>>
>> SET default_table_access_method = 'heap';
>> CREATE TABLE tableam_parted_a_heap2 PARTITION OF tableam_parted_heap2 FOR VALUES IN ('a');
>>
>> SET default_table_access_method = 'heap2';
>> CREATE TABLE tableam_parted_b_heap2 PARTITION OF tableam_parted_heap2 FOR VALUES IN ('b');
>>
>> CREATE TABLE tableam_parted_c_heap2 PARTITION OF tableam_parted_heap2 FOR VALUES IN ('c') USING heap;
>> CREATE TABLE tableam_parted_d_heap2 PARTITION OF tableam_parted_heap2 FOR VALUES IN ('d') USING heap2;
>>
>> It seems pretty clear that tableam_parted_heap2, tableam_parted_d_heap2
>> would be stored via heap2, and tableam_parted_c_heap2 via heap.
>>
>> But for tableam_parted_a_heap2 tableam_parted_b_heap2 the answer isn't
>> quite as clear.  I think it'd both be sensible for new partitions to
>> inherit the AM from the root, but it'd also be sensible to use the
>> current default.
> 
> Given that many people expected this behavior to be the sane one in other
> cases that came up, +1 to go this way.

Reading my own reply again, it may not be clear what I was +1'ing.  I
meant to vote for the behavior that David described in his reply.

Thanks,
Amit



pgsql-hackers by date:

Previous
From: Michael Paquier
Date:
Subject: Re: Fix memleaks and error handling in jsonb_plpython
Next
From: Haribabu Kommi
Date:
Subject: Re: Inheriting table AMs for partitioned tables